Well, I have some screenshots lying around... I've uploaded them just for you. Took a pretty long time.
http://imgur.com/a/GzJ6eI have a lot typed up about what works best in Silver and Plat in detail, but posting that would only serve to make decks stale. I'll be vague and just list some cards that frequently get first even if the builds aren't optimal.
For Silver: Nova, Graboid, Forest Spirit, Lycan, BB, Lightning, Phase Dragon, Psion, Immortal, Dims, UG, Immo, Photon, Crimson Dragon, LG, GotP, RT, Nightmare, pends and pillars of most of the elements I've listed, QP.
For Plat: BH, SoFo, Discord, Damsel, Elite Wyrm, AW, Longbow, Sky Dragon, FFQ, Fire Lance, Explosion, Steal, GotP, RT, Nightmare, Nova, Physalia, Flesh Recluse, Elite Mummy, Snova, QT, Forest Spectre, Werewolf, Elite Charger, Lava Destroyer, Seraph, Minor Phoenix, Gnome Gemrider, Ruby Dragon, Cremation. To a lesser extent, other Gravity, Fire, Air, Death and Entropy cards (useless ones not included) and their towers/pends. Less useful cards are not as detrimental here as in Silver. Fractal has tons of potential, but few know how the AI works. Have seen some #1 decks with it though.